Formed in 1962, the Group aims to challenge, re-define and develop standards of care in all controversial areas of breast cancer diagnosis and therapy, including rare conditions such as male breast cancer. The Group researches long-term outcomes and follows all patients throughout their lives.


  • Breast Group

    Collection of Studies

    Between 1963 and 1974, the EORTC Breast Cancer Group (BCG) conducted a number of studies that led to practice changing development in hormone therapy in patients with breast cancer. The group was the first to demonstrate how nafoxidine stops pre-cancerous growths in postmenopausal women. By 1974, the EORTC BCG tested a combination treatment of tamoxifen and two alternating chemotherapies (AV and CMF). The results demonstrated that this treatment led to higher response rates and complete remission rates, stimulating more research into treating breast cancer with combined endocrine and chemotherapy.

  • Breast Group

    EORTC 10801 – Phase III trial comparing mastectomy to tumorectomy.

    A landmark EORTC study that compared two treatment regimens in patients with stage II breast cancer, and found that although mastectomy was slightly better at local control, it did not translate to better survival rates compared to breast-conserving therapy. This finding was important and changed the standard of practice for patients overall quality of life, while at the same time helped clinicians better inform their patients of their options.


  • Quality of Life Group

    Health-related quality of life in survivors of locally advanced breast cancer.

    An international randomized controlled phase III trial.

    EORTC study comparing two treatment regimens (dose-intensive chemotherapy versus standard chemotherapy of a combination treatment of yclophosphamide, epirubicin and fluorouraci, prior to operation), in patients with locally advanced breast cancer. Results showed that patients assigned to dose-intensive treatment had significantly lower health-related quality of life (HRQOL) scores during the first three months, but scores returned to near baseline with no difference between groups after 12 months. This was the first randomized trial to show that dose-intensive treatment may lead to temporary reduction of HRQOL scores.

  • Radiation Oncology Group

    EORTC 22881/10882 – Phase III study in the conservative management of breast carcinoma by tumorectomy and radiotherapy: assessment of the role of a booster dose of radiotherapy.

    Joint study of the EORTC Radiotherapy Cooperative Group and the EORTC Breast Cancer Cooperative Group

    Since the introduction of breast-conserving treatment, various radiation doses after lumpectomy have been used. This EORTC study investigated the effect of additional radiation (radiation ‘boost’) on overall survival, local control, fibrosis (development of scar tissue) in patients with stage I and II breast cancer who underwent breast conserving therapy. After surgery and primary radiation, patients were assigned to received a radiation boost or no boost. In this 20 year follow up, results showed that a radiation boost after whole-breast irradiation, has no effect on long-term overall survival of the patient, but can improve local control, with the largest absolute benefit in young patients, although it increases the risk of moderate to severe fibrosis. In addition, it was advised that extra radiation should and can be avoided in most patients older that 60 years.


  • Radiation Oncology Group

    EORTC 22922/10925 – Phase III randomized trial investigating the role of internal mammary and medial supraclavicular (IM-MS) lymph node chain irradiation in stage I-III breast cancer.

    Joint study of the EORTC Radiotherapy Cooperative Group and the EORTC Breast Cancer Cooperative Group.

    There was a renewed interest in irradiation of regional lymph nodes in patients with breast cancer. However, conflicting evidence on the efficacy and toxicity of irradiation of lymph nodes led to uncertainties on its merit as a treatment for breast cancer. Therefore, to explore the effect of elective internal mammary and medial supraclavicular lymph-node irradiation on overall survival, EORTC studied this in breast patients between 1996 and 2004 with a median follow up of 10.9 years. Breast cancer patients who had undergone mastectomy or breast-conserving surgery and axillary dissection either received regional nodal irradiation or did not. Results showed that in patients with early-stage breast cancer, irradiation of the regional nodes, improved disease-free survival and distant disease-free survival and reduced mortality.


  • Breast Group

    EORTC 10981/22023 – After Mapping of the Axilla: Radiotherapy Or Surgery AMAROS.

    EORTC study comparing two treatment regimens in breast cancer patients with positive sentinel node biopsy, found that axillary radiotherapy is an effective alternative to axillary dissection in regional control of this tumour. Axillary radiotherapy helps bypass health complications caused by lymph node removal.


  • Imaging / Breast Group

    EORTC 10041 – MINDACT (Microarray In Node-negative and 1 to 3 positive lymph node Disease may Avoid Chemo Therapy): A prospective, randomized study comparing the 70-gene signature with the common clinicopathological criteria in selecting patients for adjuvant chemotherapy in breast cancer with 0 to 3 positive nodes.

    From 2007 to 2011, EORTC enrolled 6 693 breast cancer patients from 112 hospitals across 9 countries. This EORTC study found that the 70-gene signature MammaPrint® is an effective prognostic assessment tool for patients with node-negative or 1-3 node positive early-stage breast cancer. These patients can be safely spared adjuvant chemotherapy (post-operation), without affecting their long term outcome. This finding could substantially optimize the use of additional chemotherapy, sparing unnecessary toxicities in patients. This breakthrough clinical trial is an example of international, academic, and multi-disciplinary leadership and achievement in breast cancer research. It is also a clear illustration of an integrated public, private and patient group collaboration.


  • Dec-74
  • Dec-92
  • Apr-05
  • Jan-15
  • Jul-15
  • Oct-15
  • Sep-17


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